The present invention relates to a crankshaft support structure in a two-stroke engine.
In the conventional two-stroke engine (as disclosed in Japanese Patent Examined Publication No. 56-53123 and Utility Model Unexamined Publication No. 58-112799 and so on), lubrication in a ball bearing for supporting a crankshaft is performed with a lubricant contained within a fuel. Therefore, the conventional fuel should contain a lubricant, thereby producing exhaust gas containing a lot of white smoke, which pollutes the air.
Further, an oil passage must be provided within a cylinder block, for guiding the lubricant contained in the mixed gas (fuel) toward the position of the ball bearing for supporting the crankshaft, which makes the structure disadvantageously complex.